Closure to 'Influence of Sample Disturbance on Estimated Side Resistance of Driven Piles in Cohesive Soils'

摘要

The writers place great importance on the concept of mobilized un-drained strength, s_(uo)(mob), in Eq. (1) of the discussion to calculate the undrained stability of long embankments. The discussers state that Eq. (1) of the discussion is independent of the plasticity index, I_p. The discussers apply this concept to the behavior of driven piles in Eq. (5) of the discussion. In Fig. 1, the writers present the empirical relationship between σ'_p/s_(ufv) and I_p from Mayne and Mitchell (1988) combined with the Bjerrum (1973) correction factor, μ, to calculate s_(uo)(mob). Data from normally consolidated soils from Bjerrum (1954) combined with μ are included. The factor μs_(ufv)/σ'_p = s_(uo)(mob) is plotted with respect to I _p showing significant variations of s_(uo)(mob) with I_p, most significantly for I_p <50%. The simplified relationship in Eq. (1) of the discussion does not appear to be merited and the use of Eq. (1) in the discussion is not an improvement to the Mayne and Mitchell (1988) relationship combined with Bjerrum's (1973) correction factor.